Similar to having done for the mid-point and trapezoid quadrature rules,we obtain alternative estimations of error bounds for the Simpson＇s quadrature rule involving n-time（1 ≤ n ≤ 4） differentiable mappings and ...Similar to having done for the mid-point and trapezoid quadrature rules,we obtain alternative estimations of error bounds for the Simpson＇s quadrature rule involving n-time（1 ≤ n ≤ 4） differentiable mappings and then to the estimations of error bounds for the adaptive Simpson＇s quadrature rule.展开更多
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor...Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation.展开更多
单变量维数缩减法可以高效、准确地进行结构响应矩的分析。与传统的一阶可靠度算法FORM(First Order Reliability Method),二阶可靠度算法SORM(Second Order Reliability Method)相比,该方法不需要响应的导数,也不需要迭代搜索最可能失...单变量维数缩减法可以高效、准确地进行结构响应矩的分析。与传统的一阶可靠度算法FORM(First Order Reliability Method),二阶可靠度算法SORM(Second Order Reliability Method)相比,该方法不需要响应的导数,也不需要迭代搜索最可能失效点。然而近期的研究发现,该方法中基于矩的积分方法MBQR(Moment Based Quadrature Rule)在积分点增加之后求解线性方程组时,会出现系数矩阵的奇异性并导致数值结果不稳定,从而影响了该方法的效率和精度。提出了归一化的基于矩的积分方法,有效地解决了数值求解过程中的不稳定问题。利用降维法求解结构响应统计矩,并通过Pearson系统计算响应的概率密度函数,从而获得失效概率。算例表明了本文方法的计算效率和精度。展开更多
基金Supported by the Natural Science Foundation of Zhejiang Province（Y6090361）
文摘Similar to having done for the mid-point and trapezoid quadrature rules,we obtain alternative estimations of error bounds for the Simpson＇s quadrature rule involving n-time（1 ≤ n ≤ 4） differentiable mappings and then to the estimations of error bounds for the adaptive Simpson＇s quadrature rule.
文摘Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation.
文摘单变量维数缩减法可以高效、准确地进行结构响应矩的分析。与传统的一阶可靠度算法FORM(First Order Reliability Method),二阶可靠度算法SORM(Second Order Reliability Method)相比,该方法不需要响应的导数,也不需要迭代搜索最可能失效点。然而近期的研究发现,该方法中基于矩的积分方法MBQR(Moment Based Quadrature Rule)在积分点增加之后求解线性方程组时,会出现系数矩阵的奇异性并导致数值结果不稳定,从而影响了该方法的效率和精度。提出了归一化的基于矩的积分方法,有效地解决了数值求解过程中的不稳定问题。利用降维法求解结构响应统计矩,并通过Pearson系统计算响应的概率密度函数,从而获得失效概率。算例表明了本文方法的计算效率和精度。
